Messages in this thread Patch in this message | | | From | "Rafael J. Wysocki" <> | Subject | Re: [PATCH] kexec: fix pci device initialization fail after kexec (2.6.23-rc2). (Related to e1000 doesn't resume properly from standby) | Date | Mon, 6 Aug 2007 16:50:15 +0200 |
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On Monday, 6 August 2007 15:42, Joonwoo Park wrote: > Hi. > I think that the pci_set_power_state() has bug. > The specification says that some delays is required.
And they are in place, AFAICS (from drivers/pci/pci.c):
/* Mandatory power management transition delays */ /* see PCI PM 1.1 5.6.1 table 18 */ if (state == PCI_D3hot || dev->current_state == PCI_D3hot) msleep(pci_pm_d3_delay); else if (state == PCI_D2 || dev->current_state == PCI_D2) udelay(200);
> Simon, please can I know whether it works to you? > It is seems to the things are related. > > Joonwoo Park. > > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c > index 37c00f6..9f78064 100644 > --- a/drivers/pci/pci.c > +++ b/drivers/pci/pci.c > @@ -493,8 +493,14 @@ pci_set_power_state(struct pci_dev *dev, pci_power_t state) > * restore at least the BARs so that the device will be > * accessible to its driver. > */ > - if (need_restore) > + if (need_restore) { > + /* The specification also says that "Must ensure that all of > + * its PCI signal drivers remain disabled for the duration of > + * the D3hot to D0 Uninitialized state transition". > + */ > + msleep(10);
It's too late for the delay.
> pci_restore_bars(dev); > + } > > return 0; > }
Greetings, Rafael
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